When it is a minor failure and can be easily fixed by swapping out the faulty product, the impact on a company’s brand and its bottom line may be minimal. However, when those IoT devices are installed in hard to reach places or in harsh environments, the impact can be serious and even harmful to the user. When these devices fail, a company’s success may be on the line.

The threat of device failure is very much a reality today as the spread of the IoT picks up steam and devices find their way into some highly intriguing applications. In smart farming, for example, IoT devices are being used to track moisture levels in soil, weed crops, and help chicken eggs hatch. They are even being used to monitor the health of cows.

Figure 1. Smart cows have an implanted IoT device that is used to track their behavior and other important factors like temperature. IoT tags are also used to help track cow activity and well-being 24 hours a day.

In the case of “smart cows,” IoT sensors are surgically implanted in multiple locations under the cow’s skin (Figure 1). Once in service, the sensors are expected to operate without fail for at least three years. During that time, they track a range of things, such as the cow’s location, its behavior and even its temperature, which is often considered a leading indicator of disease.

Because the sensors are located inside the cow, they can’t be easily accessed in the case of a malfunction. The size, weight and tendency of cows to rub against objects causes concern for disrupting connectivity. What happens to a sensor when an adult cow, weighing upwards of 1,800 lbs, decides to rub a part of its body where a sensor is located?

This is a valid question and it points to a key differentiator of successful IoT devices. These devices are designed not to fail—but not just in the lab under ideal test conditions, in the real world where many factors conspire to make them do just that.

Below are five common factors that make IoT devices fail in real-world environments and tips on how to navigate the pitfalls:

Network Traffic and Connectivity

There’s often hundreds of IoT devices operating within one network. On one smart farm alone, there could be a herd of cattle (each with multiple implanted IoT sensors); sensors for measuring soil, plant and environmental variables, sensors for remote animal monitoring, farm bots, and farm drones—not to mention any personal devices the farmer might be using. This congestion may impede a device’s ability to operate seamlessly. A dramatic rise in network traffic has a similar effect, forcing the IoT device to continually re-transmit data. This may cause the device’s battery to drain quicker than expected or fail to operate altogether.

To avoid these failures, manufacturers should test the ability of their IoT devices to operate normally with a traffic load comparable to that of the target environment. Additionally, all testing should be done while simulating different traffic types like streaming video or voice.

Interference

In a large smart farm operation, there may be a dense IoT population with many devices operating on the same crowded bands. This increases the likelihood of interference between the different devices. Many of these devices can’t detect one another, let alone cooperatively share the airwaves, and as a result, many will behave in unexpected ways.

To avoid these issues, coexistence testing is essential. It can help product makers determine a device’s tolerance to other radio signals and ensure that a certain level of operation is possible, despite it operating in the presence of alternate radio protocols. IoT devices should also be challenged to see if they can cope with the many amplitudes, data rates, and protocols they will likely encounter in the real world.

Roaming Difficulties

Wireless IoT devices often roam from one location to another. That can be problematic if they haven’t been designed with robust roaming algorithms to minimize roam delay and avoid outages. An outage of just a few seconds can result in a loss of valuable data. Congestion and interference have a dramatic impact on how well roaming algorithms work, making testing under real network conditions critical to preventing a device failure. Even in a smart farm scenario, implanting an IoT device in a cow only makes sense if that device can continuously provide reliable data.

Testing IoT devices for roaming handoff behavior in a variety of challenging conditions is one way to prevent this failure. Another best practice is to simulate the device’s antenna to ensure it can handle roaming, while coping with the real-world volume and traffic.

Interoperability with Network Infrastructure

One day an IoT device can work as expected, and the next it may act erratically or stop working altogether. The device is often not the issue, but rather a result of the user updating the firmware on their wireless access points. A slight change in the network infrastructure turns a perfectly working IoT device, like a sensor implanted in a cow, into one that cannot be recognized by the target environment. Fortunately, a protocol compliance test suite can provide an effective defense against this type of failure, assuming it tests against all defined functions of a device’s wireless protocol, and not just a small subset.

Security Vulnerabilities

Figure 2. Any endpoint IoT device, like a smartwatch, a medical monitoring device or even a tracking device in a cow has the potential to be hacked.

All IoT devices can be vulnerable to attack. Sometimes hackers are after data being collected. Often times; however, what they are really after is a way to exploit the device’s lax security to gain a backdoor to another network. That’s what can happen when a device is roaming and experiences interference, such as might occur when a smart cow wanders around a smart farm congested with lots of different IoT devices. The interference can overwhelm the IoT devices in the smart cow and cause it to enter fault states, resulting in long connection delays and making it temporarily vulnerable to hacking. Using a test suite with the ability to simulate roaming behavior in a cluttered RF environment is one way to avoid this scenario.

As more consumers come to rely on the power of the IoT, increasing pressure will mount on product makers to ensure their products are reliable. For those companies looking to build IoT products that won’t fail, the trick lies in thoroughly understanding a product’s deployment environment and performing the right type of testing to make sure it can withstand the factors conspiring to make it fail. Whether those devices are destined for use in a smart cow, in medical monitoring devices or anything in between, businesses that opt to make reliability a top priority are sure to ride the wave of opportunity in the growing IoT market.